Record Ice Mass Increase, Surprising Reversal of Melting Trend

For the first time in two decades, the Antarctic ice sheet has seen a significant increase in ice mass, according to a recent study led by researchers at Tongji University in Shanghai, China. The study, published in the journal Science China Earth Sciences, analyzes satellite data collected by NASA's GRACE and GRACE-FO missions between 2002 and 2023 and reveals an unexpected change in the dynamics of the Antarctic ice sheet.

• Reversal after two decades of accelerated loss

Between 2002 and 2010, Antarctica lost an average of 74 billion tons of ice annually. This loss accelerated over the next decade (2011-2020), reaching an average of 142 billion tonnes per year - a phenomenon fueled in particular by accelerated melting in the West Antarctic and Wilkes Land-Queen Mary Land (WL-QML) regions on the eastern side of the continent. However, between 2021 and 2023, the researchers observed an average increase in ice mass of 108 billion tonnes per year, an unprecedented reversal most likely attributed to an abnormal accumulation of precipitation.

• Four key glaciers at the center of the change

The analysis focused on four major ice basins in the WL-QML region: Totten, Moscow University, Denman, Vincennes Bay.

These glaciers were responsible for an accelerated mass loss of approximately 47.64 ± 8.14 gigatonnes/year over the period 2011-2020. According to the study, the loss was mainly driven by: reduction in surface mass (72.53%), increase in ice flow (27.47%). However, since 2021, the data indicate a net accumulation of ice, a surprising signal in a climate landscape dominated by negative trends.

• Impact on sea level

According to the study, changes in Antarctic ice mass have had a measurable impact on global sea level: +0.20 ± 0.16 mm/year between 2002-2010, +0.39 ± 0.15 mm/year between 2011-2020, -0.30 ± 0.21 mm/year between 2021-2023 (negative contribution, temporarily offsetting the increase). This negative contribution of the ice sheet to sea level is rare and highlights the exceptional nature of the period analyzed.

• A temporary respite or a paradigm shift?

The researchers warn that despite this temporary recovery, the long-term risks should not be ignored. The complete melting of the four glaciers studied could lead to a sea level rise of more than 7 meters - a catastrophic scenario for coastal areas around the world. "Their pronounced ablation patterns already constitute a critical climate warning signal, justifying increased scientific attention to their stability," the authors say. Titled "Spatiotemporal mass change rate analysis from 2002 to 2023 over the Antarctic Ice Sheet and four glacier basins in Wilkes-Queen Mary Land," the study is signed by Wei Wang, Yunzhong Shen, Qiujie Chen, Fengwei Wang and Yangkang Yu.